Introduction
Some applications of atomic force microscopes require that the microscope
head be portable or in a "stand alone" configuration. Examples are:
- When a large sample that cannot be cut up, such as a plate of glass,
must be scanned with the AFM.
- If the AFM must be used in combination with another instrument such
as an inverted optical microscope for life sciences applications.
The AFM head that is used in the Pacific Nanotechnology products can be
easily adapted to a "stand alone" configuration.
Design
The PNI AFM scanner can be removed from the Nano-R™ or Nano-I™
microscopes with a few screws. The scanner can then be placed into a
mounting bracket that has at least one motor for probe approach as well
as some thumbscrews for controlling the probe/surface angle.
Recommended Parts List
Most of the parts required for the "stand alone" AFM scanner are available
commercially from Pacific Nanotechnology or other companies. You must have
either a Nano-R™, Nano-I™ or Ptrak3™ AFM system to build
the "stand alone" AFM head. Recommended parts for the "stand alone"
scanner are:
| Part |
Recommendation |
Comment |
| Z Thumb Screw |
Newport Corporation |
|
| Horseshoe holder |
PNI # 10-00084 |
PNI part must be modified |
| Z motor Assembly |
PNI # 81-00307 |
|
| Motor Interface Clamp |
|
Design depends on motor |
| Connector (4 pin, 6 pin) |
|
|
Building the "stand alone" scanner
Building the "stand alone" scanner is relatively simple but does require
access to a machine shop to build or modify the parts that support the
AFM scanner.
Mechanics: You can purchase and modify a horseshoe holder from Pacific
Nanotechnology. However, you can design your own horseshoe holder with a
specific footprint for the motor and thumb screws. Next, mount the motor
(requires an adapter if you use the Pacific Nanotechnology horseshoe)
and thumb screws into the horseshoe.
Electronics: Connect the hall effect position sensors and motor leads to
wires and connectors that plug into the stage interface board at the rear
of the AFM microscope. Schematics for these parts are located in the user
manual for the PNI stages.
Software: Using the X'pert™ mode software, select the correct direction
for the Z approach motor.
Picture
Below is a picture of a stand-alone AFM head constructed using an AFM scanner
from Pacific Nanotechnology. As you can see, once completed, the head can be
placed on any surface.
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